The role of Core D (Analytical and Animal Core) is to provide support to Projects 1, 2, and 3 in three areas: 1) To perform in vitro assays for pre-clinical evaluation of anti-CEA constructs and immunofusions developed in Project 2. These include: a) anti-CEA assays immunoreactivity, b) IL-2 and gamma-interferon bioassays and elisa assays to characterize and assess functional activity of the immunofusions, and c) CEA immunohistochemistry of animal tumor samples. 2) To perform animal (murine) studies for pre-clinical evaluation of novel anti-CEA bioengineered constructs and chelates developed in Projects 2 and 3. These include: a) biodistribution/imaging studies evaluating intermediate molecular weight constructs labeled with I-123 or In-111, b) biodistribution studies evaluating novel chelates conjugagted to anti-CEA antibody constructs labeled with In-111 or Cu-64, c) studies evaluating biodistribution and functional activity of engineered immunofusion constructs (minibody-IL-2 and scFv-gamma-interferon immunofusions), d) studies evaluating the therapeutic effects of 90Y labeled constructs, and e) biodistribution studies of all clinical vialed lots of antibody prior to planned clinical trials. 3) to perform core studies on clinical samples obtained from patients entered on imaging and therapy trials in project 1. These studies include: a) In-111, 90-Y and I-123 counting of blood, urine, and tissue biopsy samples, b) In-111 and 90-Y counting of bone marrow samples, c) human anti-chimeric antibody and anti-audiotape assays on blood samples, and d) HPLC analysis of blood and urine samples.